Preparation of cyano organicsulfonyl chlorides



. '2;7"'/s',61 I PREPARATION or CYANO ORGANICSULFONYL CHLORIDES FrederickComtedfirkwoqd;Mo assignor to Monsanto ('Ih emit:al Company; -St. Louis,- Mo.,-- a corporation of Dela'ware i i "NoDrawihg- "Application JuIy S,1954,

4 Claims (GlL260-465) This inVeiitionTrEIats to the preparation of cyano ofg anicsulfonyl chlorides and" morepa'rtlcula'rly pertains toennnproved processfo'r preparing-cyano or'ganic'sulfonyl chlorides from trichlorophosphazo organic acyl" For example;

. o s sulfonyl chloride can be used as an intermediatein the United States Patent preparation of alkyl substituted sulfamyl derivatives-of organic acids such as.pdin-propylsulfamyl). benzoic acidbyfreacting aprirnary or secondary amine with the cyano organicsulfonyl chloride inan alkaline medium, for-example in the presence of sodium hydroxidey-a'nd acidifying the resulting-product. The cyano. group canbe reduced: to form a: primary methyl amino group, or

it can: be reacted with an alcohol to for-m an imido ester group, or itcan be oxidized to an isocyano group which reacts with alcohols to form urethanes or with ammonia or' amin esto -form ureas, or thecyanoggroup can be utiliz ed in any other of the nitrilereactions. *Likewise the sulfonyl chloride" group can be utilized in the --prepara-. tion of an unsubstituted sulfonamidegroup as;--well?'as monoand di-substituted*sulfonamide groups, Tor in =-the preparation of esters by the reaction of the sulfonyl chloride group with an alcohol or in the preparation of numerous other group'sby utilizing the reactivity of the sulfonyl chloride group;

ln general, the process of this invention is an improved process for; preparing cyano organicsulfonyl chlorides from;trichlorophosphazo organicacyl chlorides.

The" conversion of a trichlorophosphazosulfonyll organic. acyl chlorides to a cyano organicsulfonyl chloride takes,

place according to the following reaction,

Ql P:NOS-AO C1 CISOz-A-CN Pool;

whereinvA is-za divalentorganic group. The preciselre action'mech'anics of the above conversion reaction has not' been definitelyestablished. Considerable evidence has-*beedpresentedto indicate that the conversion involves an intermolecular reaction althoughthe possibility of-an-intramolecularrearrangement or reaction has not been positively overruled. However, the process of this the'conversionof'the trichlorophosphazo acyl chloride.

invention is'not dependent upon theprecise' mechanics of (Dne'metho'dsuggested for the'conversion 'of"=a=tri-'- chlorophosplrazosulfonyl organic acyl chloride to-a cyano= organicsulfonyl chloride is to merely heat the dry solid precursor to a temperature ofat least 200 C. Another method 'sug'gestedafor 'thiscdnversionis to heatia solution of theprecursor :a' trichlorop'hosphazosulfonyl organic acyl-chloride in dry "carbon tetrachlorideto a temperature of 200 C.. or above. The latter process' would-*ofipdurse-htrve to becarried .out'under pressure.

Both of these methods suggested for achieving the deice v sired conversion reportds'ubstantially quantitative yields of the cyanoaromatic sulfonyl chloride. However; it has been fourid thafiquantities greater than" about 0.1girain mole ofthetriclilorophosphazosulfonyl organic acyl chlok ride heated accor' dingto either of the suggested merit ods give very erraticresults. :For'e'xample, the conversion will begin at 150 C. one time, 190 C.-at another timei'and" at a temperature of above 200 C. at still another"time. Also, the? erraticnature of the conversion reaction plus the exothermic nature of this "reaction makes control of the reaction temperature difiicult causinga substantial portio'n'ofthe desired product to decompose to a'cyanoorganic chloride throughtlie de- I struction of the "sulfonyl chloride group splittingoutSOz Obviously, large scale production of a cyanoorganicsulfonyl chloride because ofexcessively high temperatures.

cannot be'succe'ssfully achieved by either of the suggested"m'etl1ddsforiaccomplishing the conversion at any knownorpredictable temperature.

from the description hereinafter appearing.

It has been discovered that the conversion of memorophospha'zosulfonyl organic acyl chlorides having the formula wherein A is adivalentorganic group, to the corresponding cyano sulfonyl chloride can be accomplished by heating said trichlorophosphazosulfonyl acyl chloride in the presence of a small amount, up to 10% by Weight or more, of the desired cyanosulfony-l chloride previously prepared. The reaction can be carried out inthe presence of an inert reaction diluent which may be a 'sol vent for either the starting material or the end product. ,I-Iowever, the" diluent need not be a solvent for any of.

the chemical compounds present.

In general the process of this 200 C., adding the cyanosulfonyl chloride and heating the mixture at the desired conversion tempreature. amount of thecyanosulfonyl chloride can be added s'ince it will be the ultimate product. Excellent results can'b'e obtained by adding as little as 2.0 parts'up to 10 pa'rtsf are not involvedand consequently the formation. of cyano organic chlorides by splittingout of 'SOadoes' not take place, and the resulting formation of undesirable byproducts such as cyano organic chloride and tarry matev rials by side reactions is substantially eliminated. In

the preferred process of this invention there is used i from about 1 to 10 parts by weight of the cyanos-iilfonylchloride. per parts by-weight of the trichloro-l. phosphazo compound for satisfactory results at temperatures of from to C. More specifically the, tri-;;; chlorophos'phazosulfonyl organic acyl chloride is heated in the presence of the cyanosulfonyl chloride modenator at the predetermined temperature between 150 and;1-90 C. while removing the phosphoryl chloride -as rapidly as formed thus producing substantially pure cyanoorganic' sulfonylchloride. To facilitate the removalof theipl'i'os-"z phoryl-chloride split out during the conversion can be.t conveniently and rapidly {removed under reduc'e'd' pres l sure of from7 5 to 200 mm. Hg absolute. However, sub- Paitented Dec; 25,1 1 956i t b v invention is carrie d out by heating the trichlorophosphazosulfonyl organic chloride to the desired conversion temperature, under;

trated in greater detail in the specific exampleshereinafter appearing. p

Trichlorophosphazosulfonyl organic acyl chlorides which can be converted to cyano organic chlorides according to this invention are those having the formula wherein A is a divalent organic group. The divalent group A can be alpihatic or aromatic groups including alkyl, alicyclic including groups derived from naphthenes, aryl, alkaryl and aralkyl hydrocarbon groups as well as such groups containing nonhydrocarbon substituents such as halogens, ether and thioether substituents such as alkoxy, aryloxy, alkylthio and arylthio, nitro, amino, among others. Such groups as the hydroxy, carboxy, amino, monosubstituted amino and other reactive groups can also be present, however, such reactive groups are generally displaced during the preparation of the trichlorophosphazosulfonyl organic acyl chloride which is accomplished by reacting a sulfonyl organic carboxylic acid with phosphorous pentachloride. Although the above formula indicates the presence of only one trichlorophosphazosulfonyl group, Cl3P=NO2S-, and one acyl chloride group, the process of this invention is not limited solely thereto for compounds containing more than one of either of these groups can be employed in the process of this invention.

Typical trichlorophosphazosulfonyl organic acyl chloride reactants which can be employed in the process of this invention include among others trichlorophosphazosulfonyl acetyl chloride, 3-trichlorophosphazosulfonyl propionylchloride, trichlorophosphazosulfonyl stearylchloride, trichlorophosphazosulfonyl cyclopentane acyl Y chloride, p (trichlorophosphazosulfonyl) cyclohexane acyl chloride, p (trichlorophosphazosulfonyl) benzoylchloride, 7 trichlorophosphazosulfonyl 3 phenanthrene acyl chloride, 4 trichlorophosphazsulfonyl 1- naphthoylchloride, 5 trichlorophosphazosulfonyl 1- naphthoxychloride, trichlorophosphazosulfonyl-nicotinylchloride, di (trichlorophosphazosulfonyl) phthalylchlorides, 4,5 di(trichlorophosphazosulfonyl) 1,8 naphthalylchloride, trichlorophosphazosulfonyl cyclohexyl acetyl chloride, 5 (p trichlorophosphazosulfonylbenzoyl) propionyl chloride, trichlorophosphazosulfonyl nitrobenzoyl chloride, trichlorophosphazosulfonylchlorobenzoyl chloride, trichlorophosphazosulfonyl chlorocyclohex ane acetyl chloride, and 5-(trichlorophosphazosulfonyl)- 2 furyl chloride.

The following examples are illustrative of the process of this invention. In these'examples all parts are by weight.

Example I There is heated 429 parts of a mixture containing 263 parts p-trichlorophosphazosulfonyl benzoyl chloride and 166 parts of phosphoryl oxychloride in suitable distillation equipment at about 60565 C. and a reduced pressure of about 217 mm. Hg until about 90% of the phosphoryl chloride has been distilled off. Thereafter the temperature is increased to 190 C., 13 parts of p-cyanobenzenesulfonyl chloride are added, and POCla split out by' the rearrangement reaction is again distilled oil. The reaction medium is maintained at about 217 mm. Hg and 190 C. for about 3 hours, the pressure is then further reduced to 100 mm. Hg and held there for about one hour. The residual material is cooled to 50 C. and 156 parts of toluene is added thereto. The resulting mixture is heated to 70 C., filtered and the filter cake is washed with 56 parts of hot toluene (65 C.). There is recovered 359.3 parts of toluene solution of which 212 parts are toluene and 160 parts are p-cyanobenzenesulfonyl chlo-' ride including the 13 parts charged.

Example II The process of Example I is repeated except that 26 parts of p-cyanobenzenesulfonyl chloride are added in place of the 13 parts when the distillation temperature had reached 170 C. at 200 mm. Hg absolute. The yield of p-cyanobenzenesulfonyl chloride recovered is about Example III The process of Example I is repeated except that 6 parts of p-cyanobenzenesulfonyl chloride are added in place of the 13 parts when the distillation temperature had reached 180 C. at 200 mm. Hg absolute. The yield of p-cyanobenzenesulfonyl chloride recovered is about 95 Example I V The process of Example I is repeated except that a conversion temperature of C. and a pressure of 150 mm. Hg absolute are employed. The yield of pcyanobenzenesulfonyl chloride recovered is substantially the same.

Example ously prepared are added to the hot material in the still pot. The rate of distillation of phosphoryl chloride again increases indicating that the rearrangement reaction is taking place splitting out POC13. When the distillation of POC13 apparently stops, the pressure in the distillation equipment is reduced to about 75 mm. Hg absolute for about an hour and no heat is supplied to the still pot.

The residue in the still pot is cooled to about 50 C. and then dissolved intoluene and the resulting solution filtered. 2-cyano-5-furansulfonyl chloride can be recovered by distilling off the toluene at reduced pressure.

2-cyano-5-furansulfonyl chloride,

HC-OH can be converted to 5-(di-n-propyl) sulfamyl-Z-furoic acid, a compound similar to Benemid, by reaction with di-n-propylamine in the presence of sodium hydroxide followed by acidification with hydrochloric or sulfuric acid.

Example VI 1,8 dicyano naphthalene 4,5 disulfonylchloride is prepared by heating 0.25 mole of 4,5-di(trichlorophosphazosulfonyl) 1,8-naphthalyl dichloride obtained from .he reaction of 0.25 mole 4,5-disulfamyl-1,8-naphthoic acid and 1.25 moles of PCl5 in POCls after removing the free POC13, to about C. at 200 mm. Hg absolute in the presence of 10 parts of 1,8-dicyano-naphthalene-4,5- disulfonylchloride and removing the POCls split out as .apidly as formed. When POCl3 is no longer evolved, the residue is held at about 90 mm. Hg absolute until its temperature is about 50 C. The desired produce is obtained in an excellent yield.

Example VIl boxylic acid, by heating at 160 C. at about mm; Hg

absolute in the presence of 4% by weight of p-eyanocyclohexanesulfonyl chloride While removing the POCls evolved substantially as rapidly as formed. When POCls is no longer evolved, the pressure is further reduced to about 85 mm. Hg and there maintained until the residual material is cooled to about 50 C. The residue is the desired product.

Example VIII 4 trichlorophosphazosulfonyl-Z-nitrobenzoyl chloride, obtained by reacting 4-sulfamyl-2-nitrobenzoic acid With P015 is heated to 150 C. at about 190 mm. Hg absolute in the presence of 4% by Weight of 4-cyano-2-nitrobenzenesulfonyl chloride While removing the POC13 as rapidly as formed. When POCls is no longer evolved, the resulting residue is held at a pressure of about 100 mm. Hg absolute Without heating until its temperature reaches 50 C. The residual material, 4-cyano-2-nitrobenzenesulfonyl chloride, is produced in substantially quantitative yields.

What is claimed is:

1. In the preparation of a cyano organicsulfonyl chloride by heating a trichlorophosphazosulfonyl organic acyl chloride, the steps comprising heating a mixture containing initially said trichlorophosphazosulfonyl organic acyl chloride and at least one part by weight of the desired cyano organicsulfonyl chloride as a reaction moderator per 100 parts by weight of said tri'chlorophosphazo sulfonyl organic acyl chloride at a temperature of from 150 to 190 C. and removing the POCla as formed.

2. In the preparation of a cyano organicsulfonyl chloride by heating a trichlorophosphazosulfonyl organic acyl chloride, the steps comprising heating a mixture contai'ning initially said trichlorophosphazosulfonyl organic acyl chloride and from about 1 to 10 parts by Weight of the desired cyano organicsulfonyl chloride as a reaction moderator per parts by Weight of said trichlorophosphazosulfonyl organic acyl chloride at a temperature of from ride by heating p-trichlorophosphazosulfonyl benzoyl chlo-' ride and splitting out POC13, the steps comprising heating a mixture containing initially p-trichlorophosphazosnlfonyl benzoyl chloride and from about 2 to about 10 parts by Weight of p-cyanobenzenesulfonyl chloride as the reac-' tion moderator per 100 parts by weight of p-trichlorophosphazosulfonyl benzoyl chloride at a temperature of from to C. and a pressure of from 75 to 200 mm. Hg absolute While removing POCls as evolved.

References Cited in the file of this patent Kirsanov: Chem. Abst., vol. 46, column 1135 (1952). 

1. IN THE PREPARATION OF A CYANO ORGANICSULFONYL CHLORIDE BY HEATING A TRICHLOROPHOSPHAZOSULFONYL ORGANIC ACYL CHLORIDE, THE STEPS COMPRISING HEATING A MIXTURE CONTAINING INITIALLY SAID TRICHLOROPHOSPHAZOSULFONYL ORGANIC ACYL CHLORIDE AND AT LEAST ONE PART BY WEIGTH OF THE DESIRED CYANO ORGANICSULFONYL CHLORIDE AS A REACTION MODERATOR PER 100 PARTS BY WEIGHT OF SAID TRICHLOROPHOSPHAZOSULFONYL ORGANIC ACYL CHLORIDE AT A TEMPERATURE OF FROM 180* TO 190* C. AND REMOVING THE POCL3 AS FORMED. 